Counterexample to Néron-Ogg-Shafarevich criterion for Calabi-Yau threefolds

Tymoteusz Chmiel, Marcin Oczko

For any prime $p>5$ we construct a Calabi-Yau threefold $X$ defined over a finite extension $K$ of ${\mathbb{Q}}_p$ such that every model of $X$ over $\operatorname{Spec}\mathcal{O}_…